Fantasy baseball rule No. 595: If you think Jason Giambi is still a 30-HR guy and Milton Bradley is not injury-prone, then maybe you should try fantasy football instead.

Let’s get back to the first rule. When a player gets traded from one major-league team to another, his fantasy value has a great chance of turning upward.

It could be because he is given a new lease on life that infuses him with energy. It could be because he will be given more chances to knock in runs or win games because he is going from a bad team to a good team, or from a team who could not use him to a team that has big plans for him.

Or it could be because he is switching leagues and his new opponents do not have a book on him yet.

If you do not think this rule is legit, just look at what has happened during the past couple weeks to three players not exactly known as rivals of Albert Pujols for fantasy baseball’s MVP award.

This trio has killed more fantasy owners this season than Raid has killed bugs, yet since they switched uniforms they have actually become deserving of fantasy roster spots.

Here is a look:

Jeff Francoeur, New York Mets

This is a match made in rotisserie hell, right? No player walks less than Francoeur. No team hits fewer home runs and has a more hitter-hating ballpark than the Mets. There is no way this could work.

Well, not many thought Heidi Klum and Seal were the most compatible couple, either.

Francoeur has hit like the "Frenchy" that had back-to-back 100-RBI campaigns in 2006 and 2007 since joining the Mets. Francoeur has driven in 16 runs in his first 14 games with his new club, which is pretty impressive considering Jose Reyes is not getting on base in front of him and Carlos Delgado and Carlos Beltran are not hitting around him because all are on the disabled list.

Still, fantasy owners know Francoeur is limited. He does not steal bases (14 SB in five years), draw walks (career .309 OBP) and has slumps that last longer than Aerosmith concert tours. But he looks refreshed and renewed since getting out of Atlanta and could very well help fantasy owners in the home runs and RBI departments down the stretch.

Adam LaRoche, Boston Red Sox

Don’t expect this former Pirate to pull a Jason Bay and double his fantasy value with the Red Sox. It will be nearly impossible for LaRoche to pull off such a feat since he is not playing every day thanks to Boston’s depth at first base and designated hitter.

But early signs suggest fantasy owners should not drop LaRoche right away, either.

LaRoche had been slogging through a mediocre season with Pittsburgh—12 HR, 47 RBI, .243 batting average—when he was traded in another cost-cutting, setting-up-for-2015 deal by the Pirates. But at least he was playing every day and batting cleanup in Pittsburgh’s lineup.

For Boston, albeit in a hitter-friendly ballpark and surrounded by much better talent, LaRoche is only probably going to play against right-handed pitchers and bat seventh.

But here are three reasons to think LaRoche could be a fantasy steal from here on out:

LaRoche’s quick start: He has not needed much time to adjust to AL pitching. He is hitting .357 with a homer and three RBI in his first four games with the Sox and has looked comfortable in his new digs.

Mike Lowell’s hip: The Red Sox's starting third baseman has been missing some time due to his surgically-repaired hip acting up on occasion. Lowell might receive extra rest the closer it comes to playoff time, which would mean more Kevin Youkilis at third and more LaRoche at first.

If Lowell dives or swings the wrong way, another DL stint for him would turn into full-time at-bats for LaRoche.

LaRoche’s second-half history: Our guy has always been better after the All-Star break than before it. Between 2006 and 2008 he batted .314 with a .952 OPS and 41 homers after the break, while batting just .247 with a .775 OPS and 37 homers prior to it.

His so-so first-half numbers and quick start with Boston suggest that this pattern could continue for a fourth straight season.

Julio Lugo, St. Louis Cardinals

One of the most overpriced shortstops in the history of baseball, Lugo’s fantasy worth with Boston this season could have only gotten lower if he had died. He had only appeared in 37 games and had given fantasy owners one home run, three stolen bases, and a lot of days off.

Only a team desperate for middle infield help could have used Lugo.

The St. Louis Cardinals were that team. And now, somehow magically, almost as if an angel has showered him with mystical Garry Templeton dust, Lugo is back hitting four or five years ago when he was one of the top-10 shortstops to own in fantasy.

Four games, four runs, three RBI, one homer, one steal, and a .474 batting average.

That’s right, .474 (9-for-19).

Lugo does not have the power or the wheels he had during his glory days, but if he can play regularly and get on base with Pujols, Matt Holliday, Mark DeRosa, and Ryan Ludwick hitting behind him, averaging close to a run scored per game might well happen for him.